A mystery wrapped in a myth about the origins of humanity.A race to find an ancient pyramid hidden in plain sight.A secret so dangerous its guardians will kill to protect it.And an ancient covenant that might save the world, or destroy it completely.

In 1655 a group of explorers from the Emerald Star entered the Namibian Desert in search of an ancient relic rumored to be hidden in a secret temple. None of the crew ever returned — but stories of their mysterious demise continued to be told.In the present-day Turkish subterranean city of Derinkuyu, a strange wooden placard is discovered floating in an old well. It’s covered in the script of a language long forgotten, but Sam Reilly has seen the text before. The words suggest an ancient race might still exist, and are in the process of building a new temple.The question is — is it the same temple where Dr. Billie Swan is being held prisoner?